Sound is simply stunning, utterly brilliant BUT there is a lack of bass around the 100-200Hz where the amplifier simply doesn't hit with authority. It's not my speakers. My brother has the same setup but with Tannoy 607's and has the same problem.

I contacted Sure to see if the new revision helps but they said it sounds just the same.

Bass performance depends almost entirely on the output filter coils. Most commercially available TK2050 (or really TC2000 controller chip) based amps have inadequate output filter coils because they are very low cost designs and good filter coils does actually cost a lot of money leading to the assumption by many that the TK2050 can't produce good bass.

Second problem is that most people run them on cheap SMPS that aren't able to provide the current rise times that are needed for peak output. Running a TK2050 on batteries with a capacitor bank makes a huge difference in bass performance.